In a general configuration method of an application, a specific task is divided into relatively small functional units, each of which is processable, in a design stage of the application, and a program is created for each small functional unit. Finally, the programs are linked to each other by compilation and link operation of the programs and integrated into one application program.
In the above method, the configuration of the application is determined when the application is compiled and linked. In other words, this method is an approach in which the configuration is fixed before the application is put into a system on the premise that the environment and the state of the system on which the application is executed are fixed. This method is effective if external functions required by the application are limited to functions included in the operating system (Windows (registered trademark), MacOS, Linux, or the like) and there are no performance requirements such that an operation included in an action of the application is completed within a certain time period.
In recent years, an approach for performing a part of the link operation at the start up of the application is invented. This is an approach in which the configuration of the application is described as a definition file and the functional units are linked to each other on the basis of the description content of the definition file when the application is executed. Therefore, at the time point when the application is deployed in an execution environment, the configuration of the application is not fixed and individual functional units are present independently.
In the above method, the configuration of the application can be changed by using a setting file according to the environment in which the application is executed, so that it is possible to change the configuration relatively easier than the method in which the configuration is fixed by linking the functional units in advance.
PATENT DOCUMENT 1 (Japanese National Publication of International Patent Application, No. 2006-526209) proposes a method for defining the setting file, in which the configuration of the application is defined, as metadata, and using Glue code to adjust consistency of interfaces between functional parts.